Thread: Design-headwind
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Old 02-28-2011, 06:07 PM   #17 (permalink)
aerohead
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hard to dismiss

Quote:
Originally Posted by KamperBob View Post
Percentages can be tricky. It's all about context.

Cd1 = 0.3
Cd2 = 0.1

Cd1 is 300% *of* Cd2. [multiplicative]
Cd1 is 200% *larger* than Cd2. [additive]

Same for horsepower, and it doesn't change your bottom line as I said before.

(Call me a nit picker but an error of 100% seems hard to dismiss. I thought it was kind of humorous. I hoped you did too. If not, sorry.)

I wonder what my Cd is riding motorcycle...
Bob,I see what you mean and it's not picking nits at all.
I think I've been stuck in 'multiplicative' mode.Once a value is in the calculator I just carry it through.Lazy huh?
Is '3X' a more accurate representation of the Cd comparison? Before we get too far into this it would be nice to have clarity.
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With respect to your bike,Hoerner posted Cd 0.90 for un-faired MCs.Ouch!!!!!!!!!!!!!!!!!!
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